Slotting saw



Feb. 16, 1954 w. STERN 2,669,007

SLOTTING SAW original Filed July 25, 1948 2 sheets-sheet 1 zza Feb. 16, 1954 w. STI-:RN 2,669,007

SLOTTING SAW original Filed July 25, 194e 2 sheets-sheet 2 a a Q34@ Patented F eb. 16, 1,954

WilliamStel-n,Parkdge Ill.; assignor to Illinois# Toolewagksgcnicagc, 111., agcorpcraucmofznli nglfthis apiilicat'ion' January" This Finvention is concerned-generally with aj 5 i saw fandmore particularlylfwitli a-sawv -for 'slotfting screws.

Any-ob'je'c't of this'` invention This@ invention--contemplates the provision 'gofjj"4 a s'aw structure -or' )cutter-constructed of a lpl'lr- 'g rality of helical blade -sections --each'A ofl which? readilyI` is `replaced*where-wornl or damaged.

An object 'offthisinvention is ytc n1;)rc`v'icle ai plurality' of helical" saw or f cutter `sectic'ins lar-' ranged inregis'traticrrtoy form-'a continuous'h elif' A further 'object of rthis invention# is to provide=means ``for I securing-faV plurality l Vof helical saw' or cutter sections against-relativecircuni-" ferentialf and faxial movement *to* form la continucus helical-working edge.-l

A- more specific `-object of this vinvention is tof pro'v'de'means for resiliently securing a plurality- P25; relative movementf-toform a=`cont'finuous;-helicalof-'fsa'ivJ or cutter lsections Yin registration;A against work-ing edge:

Another# obj ect-off this invention is-ltcdevi'se" a method ofmalzinga helical fsaw'or-cutter Other and ffurther@ objects and advantages ofx the-'present invention-will \beapparent fromethe following'y description when` taken in" connection;

withl the accompanying drawingsj wherein Fig.; 1l is; a fragmentary, plan" view 'lof e'. screw',

slcmngY machine Y incorporatinggthepsaw vwhichj isithejsubjct offthis invention;v

Fig'. 21"`is' 'a fragmentary sectional viewlalongj theline 2-2 of Figui;`l

Fig. 3 is a. fragmentary along theline 3'-3 cfFigl;

Fig` f4 j'isA a sectional view of the along 'the line LA of Fig;j3

sectional Viewl taken Figi 5 is ajview in eievaticngof-a screwsicttinggonfsawing made;

a Vhelderder the screw slottingfbladeorysawr' g. '6"is a viewwin elevation"of"partsforming f Fig; 7 'is 1an enlarged fragmentary view in' hori-f zo'ntal Ysection takenfsubstantially along the linei meng'phe une a+s ofFigis.

* taken .subi stantially`v pol-ating the ysaw forming the-subie that# thsjnventicn includes a sc rewfeedmgchu :orme-rr :by-spacedcarsfreceivingctweethm rslcbuagrstationl'42 'capre/ent;1dispiacementA f the'gshanks of x"screwsfori screw" blanks l2 vande' supporting theeheacls'of-l'f'the-screws; A- coverl`v bari*Ulf-lies abovefthehead's'of the screwrelementsl in thechute and prevents them from becoming-l tilted or- -jammed "in the-chute; The chuteJ i011 is v`v supplied -fwitfh screw` elements IZ-frovm-Lany suite ablehopper vmechanism (not shown);l l

A! continuously moving screwl carrier Isf-inceivingblocks 30 Iisl vsecured jby link pli-nsv 32 "(Fig: 3)` to-'the- Silent chaink I 8;' Each blockJ `is pro-V vided With-a plurality of slots or recesses34f-for receiving the Shanks of screws I I 2 with the-heads ofthe screws resting on thetop surfaces of the- EachM block hasr half recesses or slots# at the opposite'v ends thereof to cooperate with the next blockl informing slotsv similar to# thev blocks.

fslolts A34.- Screwelemerrts' l2 received by the slots 34from the feed chute I'dthus'are spaced equally v about-thelengthlcfl the chain'ancl thefront sur-` faces -36 of" the bloc-ks intern'lediatev the recessesareinclinedslightly asjbesgt may be seen `in Fig.V 7

to` facilitate A reception# of screw elements from the ufeedI chute; 5

The screw carrier blocks' 301have beveled` de# pending -pcrtions 38`fsldably suppcrtedby, and" interttin'g'withjthe ybeveled-rear edge of aconfvftinuous-*track-4D"1underlyng the Silent chain I8.

zei Amid-down plate ccis exec' to the backiu1; blockll' Joy means such as boltl 'lgand is p ro` videdki with, guide projectionsv ucoo-perating. with complementarystructure 152'fcrmedin the tons; ofthe blocks 30;' The- 'upper outerA` edge of the. back-un block -44 isformed with a recessed pcrtion' .'ireceiving rearwardlyjprojecting guide ange'sof ythe 4blcck-s overlying v the guide strucj turer52 The blocks further 'erre supported from beneath' by a ,strip 56.

infFigs". 3and 7, aguide surface and VEarear .sup-

port for thexlinks ofthe chain vI8 at the sloiA:i ng y y The front face of 'the 5 back-upfblcck'dd ispositioned to formasshown the screw elements while they are being slotted. The hold-down mechanism comprises a roller chain i60 `passing over idler sprockets 64 journaled on studs 66 `carried by mounting ilanges 68 of a block '|0 bolted to a bracket 'I2 upstanding from the bed plate 26. The lower flight or reach of the roller chain 60 passes beneath rollers 14 carried by blocks 16 secured to rods T8 slidably mounted in a forwardly projecting flange 80 of the block '10. Coil springs 82 encircle the rods 18 and are compressed between the flange 80 and the blocks 16 to cause the rollers 14 to urge the lower flight or reach of the chain 60 downwardly against the heads of the screws |2 to clamp them in the recesses in the screw carrying blocks as they pass the slotting station.

The slotting mechanism preferably comprises a first mounting block 84 adjustably secured on the bed :plate '26 by means such as bolts 86 received in transversely elongated slots 88. The bolt-in-slot mounting allows the block 84 to be adjusted toward and from the screw carrying blocks 30 as they are moved by the chain I8 past the slotting station 42. The mounting :block 84 is provided with an upstanding, right vangularly disposed flange v having slots 92 for receiving mounting bolts 94 by means of which a slide guide 06 adjustably is secured to the first mounting block 58 for adjustment in a plane perpendicular to the bed plate and axially of the screws at the slotting station. A slide 98 is .provided with a dovetail channel interfltting with the slide guide 96 and is provided at one end with an L-shaped bracket portion |00 extending past the end of the ange -90 of the first mounting block 04. The bracket portion |00 carries an adjusting screw |02 threaded therethrough and abutting against the end of the ange. The position of the slide 98 may be determined by adjusting the screw |02. Following adjustment, the slide S8 can be locked in position by means of a locking screw |04 threaded through the slide and impinging against the guide 96.

The slotting saw |06, as seen in Figs. 4-6, comprises a helical saw blade |08. The saw blade consists of a plurality of segments or centrally apertured disks |09 each twisted in an axial direction to form a helix, the helixes of the plurality of disks being of the 'same pitch and diameter, and the disk edges being registered to form the complete blade. The helical segments are brought into perfect registration by threading them into a spring-like holder ||0 which consists of a helix, the space :between the adjacent convolutions corresponding to 'the thickness of the segments of the saw blade |08 and the width of the material forming the helical holder corresponding to the distance between adjacent convolutions of the saw blade. The assembled helical saw blade and holder are mounted on a sleeve ||2 between collars ||4 and ||6 having helically formed inner faces ||0 and |20 complementary to the outer faces of the saw blade |08, the outer faces |22 and |24 of the collars being flat. The sleeve ||2 is provided at one end with an integral, enlarged head portion |26 having opposed flat, or chordal surfaces |28 adapted to be engaged by a wrench or the like. The opposite end of the sleeve |2 is provided with external threads |30 'and an internally threaded nut or collar |32 having opposed ilat, or chordal wrench engaging surfaces |34 is threaded thereon. The nut |132 is threaded onto the'sleeve H2 sufficiently far to clamp the re- 75 Thesaw blade as formed herein readily is desilient holder ||0, saw blade |08, and collars ||4 :and H6 sufficiently tightly to insure their rotation along with the sleeve.

The sleeve |2 is mounted on a driving shaft |36 and is keyed thereto for rotation therewith. The shaft |36 `is journaled in suitable bearings |38 in forwardly extending arms |40 of the slide 98 and is provided with a spur gear |42 meshing with a cooperating gear of suitable drive mechanism (not shown). The gear |42 and a nut |44 threaded on the other end of the shaft |36 secure the shaft against axial movement.

The saw segments |09 originally consist of individual, at metallic rings or apertured disks. The rings fist are sheared or split and then are bent into helical form. After being bent into helical form, the saw segments are heat-treated, placed in a suitable helical holder, and drawn to relieve hardening stresses. The segments then are arranged in axial alignment with the ends of adjacent segments in registration by threading them into the holder |0 and clamping them between the collars ||4 and H6 on the sleeve ||2. After the sleeve has been mounted on the shaft |36 between the arms |40, teeth |46 are ground in the periphery of the several saw blade segments to form the saw |06.

In order to slot screw elements, a continuous succession of threaded screws or screw blanks is delivered by the gravity feed chute l0 to the blocks 30 carried by the continuously moving chain |6 and are received in the recesses 34 in the blocks in the same orientation and inclination as they are delivered at the end of the chute. As the continuously moving chain I8 carries the screw elements to the slotting station 42, they pass beneath the roller chain 60 and are clamped in the recesses 34 thereby. The saw |03` is mounted with its axis inclined slightly relative to the path of movement of screw elements I2 carried by the blocks 30 and the pitch of the saw blade is made equal to the spacing between successive screw elements carried by the blocks30. The speed of the conveyor chain I8 is made proportionate to the lead and speed of rotation of the saw blade so that once a screw element has been engaged by the saw blade it will remain in engagement therewith until it has reached the opposite end of the blade. As best may be seen in Figs. 7 and 8, the relative inclination of the saw blade axis and the path of screw elements carried by the blocks, and the proportionate speed of the saw blade and screw elements causes each screw element relatively to approach the axis of the saw blade. Thus the saw blade removes successive increments of material from the shank of each screw element as it moves continuously past the saw to provide the iinal inclined Vslot |48 in the screw element shank.

After having slots |48 completed therein, the screw elements |2 leave the slotting station and no longer are engaged by the hold-down chain 60. The screw heads then are engaged by a surface of an ejector |50 inclined relative to the lpath of screw elements carried by the blocks and overlying the path to remove screw elements from the blocks.

.paratus (neither shown).

The virtues of the screw slotting machine The screw elements then may drop into a container or be supplied to other apformed from flat to helical form without excessive stress and strain due to the relatively short lengths of metal acted on, the saw blade, if damaged, readily is replaced in part, and the blade holder can be utilized indeiinitely with a succession of blades.

The specific example shown and described herein is for illustrative purposes only. Vario-us changes may be made in the method of manufacturing the saw blade without departing from the spirit and scope of the invention as set forth in the following claims.

I claim:

l. A saw comprising a saw arbor of uniform diameter, a helical saw blade arranged coaxially about said arbor, a helical blade holder substantially complementary to and intertting with said blade, and means for mounting said blade and holder on said arbor for rotation therewith.

2. A rotary cutter comprising an arbor, a blade including a plurality of helical blade sec tions each being substantially fiat and coiled edgewise and having a sharpened material working edge, means including a holder having a helical slot therein for arranging the blade sections in registration to form a continuous helical blade, and means for mounting said blade and holder on said arbor.

3. A saw comprising a saw arbor,l a helical slotting blade arranged coaxially about said arbor, a helical spacer intertting with the convolutions of said helical blade, end members each having a helical face-abutting the end surfaces of said blade, and means for mounting said blade, helical spacer, and end members on said arbor for rotation therewith.

4. A rotary cutter comprising a blade including a plurality of helical blade sections each having a sharpened material working edge, a spacer having a helical slot therein receiving said blade sections in registration to form a continuous helical blade, a pair of end members each Y having a helical face intertting with an end surface of said helical blade, and means for mounting said blade, spacer, and said end members together as a unit.

5. A slotting saw comprising a helical slotting blade, a resilient helical spacer interfitting with said blade and spacing the convolutions thereof from one another, the convolutions of said spacer normally being spaced apart farther than the thickness of said b1ade, a pair of end members each having a helical inner face complementary to an end face of said blade, and means for clamping said blade, spacer, and end mem bers together to compress said spacer and grip said blade between the convolutions oi said spacer and between said spacer and said end members.

6. A slotting saw comprising a saw arbor, a saw blade including a plurality of helical blade segments, a resilient helical spacer arranged coaXially with said arbor and aligning said blade segments in registration to form a continuous helical blade, end members complementary to the ends of said blade and spacer, and means for applying axial force to said end members to compress said resilient spacer and grip said blade between the turns of said spacer and said end members.

7. A slotting saw as set forth in claim 6 wherein the axial force applying means comprises an enlarged head on one end of said arbor and a nut threaded on the other end of said arbor.

8. A slotting saw comprising a cylindrical saw arbor of uniform diameter, a saw blade having a toothed periphery and including a plurality of helical blade sections each being substantially nat and coiled edgewise, a resilient helical spacer intertting with said blade and spacing the convolutions thereof from one another, the convolutions of said spacer normally being spaced apart farther than the thickness of said blade, a pair of end members each having a helical inner face complementary to an end face of said blade, and means for clamping said blade, said spacer and said end members together on said arbor to compress said spacer and grip said blade between the convolutions of said spacer and between said spacer and said end members.

WILLIAM STERN.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 938,158 Lucas Oct. 26, 1909 1,250,377 Stevens Dec. 18, 1917 1,473,374 Konig Nov. 6, 1929 2,415,271 Baumann Feb. 4, 1947 2,439,422 Fear Apr. 13, 1948 FOREIGN PATENTS Number Country Date 161,632 Great Britain Apr. 15, 1921 

